80-17×4:20-380:20+90×40:120=
80-17×4:20-380:20+90×40:120=80-68:20-19+3600:120=80-3.4-19+30=87.6380:20+90×40:120
80-68:20-380:20+3600:120=80-3,4-19+180=237,6